Switchboard wiring



1941- P. s. GRAHAM 2,253,700

SWITCHBOARD WIRING Filed March 7, 1940 WITNESSES:

INVENTOR F 11/ Graham Patented Aug. 26, 1941 Paul S. Graham, Turtle Creek, Pa, assignor to Westinghouse Electric & .Manufacturing Company, East Pittsburgh,

Pennsylvania Pa., a corporation of Application March 7, 1940, serial-Namath Claims.

My invention relates, generally, to switchboard wiring and, more particularly, to the wiring of switchboards having swinging panels or doors.

In the wiring of switchboards having swinging panels or doors it is necessary to provide flexible wire loops for connecting between the wires on the swinging member and those on the fixed member. 'Heretofore, the wiring cleats for holding the wires in position have been made of two strips, of substantially the same width, between which the wires are clamped. As the swinging member swings out and back on its hinges, the connecting wire loop flexes out to approach a straight line and returns to its loop form. In so doing the wire necessarily bends back and forth at the cleats. With cleats of substantially he same width the wire bends back and forth at the same point over a relatively wide angle. If the swinging member is operated frequently there is danger of the wire breaking at the point of bending.

An object of my invention, generally stated, is to provide an improved wiring cleat for holding flexible wires which are subjected to bending.

A more specific object of my invention is to decrease the likelihood of breakage of flexible wires which interconnect relatively movable members.

Other objects of my invention will be explained fully hereinafter or will be apparent to those skilled in the art.

According to my invention, the cleating device for holding the flexible wires in position comprises two strips of unequal widths between which the wires are clamped to form flexible loops. With strips of different widths, each wire bends back and forth at two points alternately, thereby decreasing the angle of bending and the likelihood of breakage of the wire.

For a fuller understanding of the nature and objects of my invention, reference may be had to the following detailed description, taken in conjunction with the accompanying drawing, in which:

Figure l is a view, partially in plan and partially in section, of a portion of a switchboard structure embodying my invention and showing a swinging panel in the closed position;

Fig. 2 is a view, in elevation, of the structure shown in Fig. 1;

Fig. 3 is a view, similar to Fig. 1, showing the swinging panel in the open position; and

Fig. 4 is a view, in plan, of a pair of wire cleats constructed according to the prior art and showing the bending action on the wire.

Referring to the drawing, and particularly to Fig. l, the switchboard structure shown therein comprises portions of a stationary panel l0 and a swinging panel H which swings on a hinge l2. The panels in and II may be composed of steel or other suitable material for enclosing and supporting switchboard apparatus.

In order to make connections from a terminal block H on the panel Hi to apparatus mounted on the swinging panel, it is necessary to provide flexible conductors M for interconnecting between the stationary panel l0 and the swinging panel ii. As shown in Fig. 1, each wire I4 forms a loop i5 when the swinging panel H is in the closed position and, as shown in Fig. 3, the loop i5 is opened out when the swinging panel is in the open position.

In accordance with the usual practice, the wires M are held in position on the panels by wiring cleats it between which the wires are disposed. One of the wiring cleats I6 is mounted on the swinging panel II by a bracket 11 and the other cleat is mounted on the fixed panel ill by a bracket H3. The loop I5 is formed between the cleats 16.

In order to decrease the likelihood of breakage of the wires l4 when the panel II is swung back and forth, each one of the cleats i6 is composed of a pair of strips 2| and 22 which are of unequal widths instead of the same width, as is the usual practice. As shown, the strip 2| is substantially wider than the strip 22, the strip 2| being approximately twice the width of the strip 22. The strips 2| and 22 are drawn together by bolts 23 to clamp the wires l4 firmly.

As shown in Fig. 1, the wire I4 is bent at the points 24 and 25 when the swinging panel H is closed. As shown in Fig. 3, the bending takes place at the points 26 and 21 when the panel II is open. Thus, the wire has straightened at the points 24 and 25 and the bending transferred to the points 26 and 21 as the panel H is opened. When the panel H is again closed, the wire straightens at the points 26 and 21 and bends at 24 and 25. In this manner the wire bends at the different points alternately and not at the same point all the time as is the case when the strips of the wiring cleat are the same width, as shown in Fig. 4.

Furthermore, the angle of bending at any one point is materially reduced, as will be seen by comparing Fig. 4 with Figs. 1 and 3. Therefore, the likelihood of breakage of the wire by the bending action is decreased by utilizing the wiring cleats having strips of unequal widths, as herein described.

While I have illustrated the improved Wiring cleats as applied to switchboard panels, it will be understood that wiring cleats constructed according to my invention may be utilized with apparatus of other types, as Well as in switchboard structures. Also, the strips of unequal width which form the cleat may be reversed from the positions shown in the drawing, that is, the narrow and wide strips may be interchanged, if desirable, because of space limitations.

Since numerous changes may be made in the abovedescribed construction, and diflerent embodiment of the invention may be made without departing from the spirit and scope thereof, it is intended that all matter contained in the foregoing description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. In a switchboard structure, in combination, a stationary member, a swinging member, a flexible wire interconnecting said members, and oppositely disposed wiring cleats for holding said wire in position, each wiring cleat comprising a pair of strips disposed in spaced relation, the adjacent edges of said wiring cleats being stepped to cause the wire to bend at different points alternately, thereby reducing the angle of bending of the wire as the swinging member is moved back and forth.

2. In a switchboard structure, in combination, a stationary panel, a hinged swinging panel, a flexible conductor interconnecting said panels,

and oppositely disposed wiring cleats for holding said conductor in position, each wiring cleat comprising a pair of strips between which the conductor is disposed, one of said strips being substantially wider than the other and having one edge offset from the other, the other edges being in alignment, and means for drawing said strips together to hold the conductor.

3. In a switchboard structure, in combination, a stationary panel, a hinged swinging panel, a flexible conductor enterconnecting said panels, and wiring cleats for holding said conductor in position, each wiring cleat comprising a pair of strips between which the conductor is disposed, one of said strips being approximately twice the width of the other, and means for drawing said strips together to hold the conductor.

4. The combination with a stationary member, a hinged member and a flexible conductor interconnecting said members, of means for reducing the angle of bending of the conductor Where it is connected to said members, said means comprising a pair of strips for securing the conductor to each member, said strips having their adjacent edges offset.

5. The combination with a stationary member, a hinged member and a flexible conductor interconnecting said members, of means for reducing the angle of bending of the conductor where it is connected to said members, said means comprising a pair of strips for securing the conductor to each member, said strips having their adjacent edges oifset by an amount equal to or greater than the width of the conductor.

PAUL S. GRAHAM. 

